Large Thermopower in a Layered Oxide NaCo_2O_4

I. Terasaki; Y. Sasago; K. Uchinokura

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Large Thermopower in a Layered Oxide NaCo_2O_4

I. Terasaki·Y. Sasago·K. Uchinokura

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Abstract

A transition-metal oxide NaCo_2O_4 is a layered oxide in which CoO_2 and Na alternately stack along the c axis. Recently we have found that this compound shows unusually large thermopower with low resistivity, which is comparable to those of Bi_2Te_3. The negative transverse magnetoresistance and the strongly temperature-dependent Hall coefficient suggest that electron correlation dominates the conduction mechanism in NaCo_2O_4.

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I. Terasaki, Y. Sasago, K. Uchinokura. 1999-03-10. Large Thermopower in a Layered Oxide NaCo_2O_4. https://arxiv.org/abs/cond-mat/9903162

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